Ok, semi-silly question here. I've got a 350 Vortec block from a 96 Chevy pickup and i was wondering if it was a reverse flow or not. Does anyone know? The best I can tell with the casting numbers is that it's just a vortec motor, not an LT motor (reverse flow right?). I am starting to piece meal my motor together bit by bit and I didn't want to screw something as important yet as simple as this up. How can I tell the difference? Any help would be appreciated. Thanks!

I think what you are talking about is the direction that the water pump turns because of the serpentine belt. The engine turns in the same direction only the water pump turns backwards. Not all serpentine systems are this way so just check to see if your waterpump is being turned CW or CCW. Everything else will bolt up.

Sorry, yes, I was talking about the water pump. When I got the motor, everything was disconnected already. It didn't have any accessories other than the water pump still bolted to it and the water pump will spin both ways. so.. hmm..

Sorry, yes, I was talking about the water pump. When I got the motor, everything was disconnected already. It didn't have any accessories other than the water pump still bolted to it and the water pump will spin both ways. so.. hmm..

Now wait a minute. The "reverse flow" engines push the water through the heads first then into the block. The water pump is driven by gearing to the camshaft. These were in the 92-96 Vettes and Impala SS cars and a few others.

This has nothing to do with the reverse rotation water pumps of the serpentine belt systems which is still the conventional block to heads delivery system.

I think your motor from the factory with the stock serpentine belt system run the water pump back wards (reverse rotation), if you don't run the stock serpentine belt system, you will need a older non reverse rotation flow water pump. (witch I would run, the stock serpentine belt system, it will work off the chevys 4.3 V6 & V8s)

Ok, but I can't run a reverse flow water pump on a V-belt. The rotation of the belts won't allow it. Can I put a standard rotation water pump on this thing or does it require a reverse rotation? If I cannot put a standard rotation water pump, then I will have to start scouring the junk yards for a serpentine belt system.

Ok, but I can't run a reverse rotation water pump on a V-belt. The rotation of the belts won't allow it.

Correct

a serpentine belt system needs a reverse rotation water pump, if you don't run the stock serpentine belt system, and run a V belt setupyou will need a older non reverse rotation flow water pump, Old Style Water Pump.

with the V belt system you just need a standard rotation water pump, old style, (if I'm wrong someone correct me) why not run a chevy 4.3 V6 or chevy V8 serpentine belt system ? if you run the serpentine belt system with the Reverse rotation water pump that come with the serpentine belt system your ok. the serpentine belt system fits & gets rid of V belt setup.if your wanting to keep the stock look and run the V belt, you need a older non reverse rotation flow water pump, the Old Style Water Pump..

a serpentine belt system needs a reverse rotation water pump, if you don't run the stock serpentine belt system, and run a V belt setupyou will need a older non reverse rotation flow water pump, Old Style Water Pump.

with the V belt system you just need a standard rotation water pump, old style, (if I'm wrong someone correct me) why not run a chevy 4.3 V6 or chevy V8 serpentine belt system ? if you run the serpentine belt system with the Reverse rotation water pump that come with the serpentine belt system your ok. the serpentine belt system fits & gets rid of V belt setup.if your wanting to keep the stock look and run the V belt, you need a older non reverse rotation flow water pump, the Old Style Water Pump..

although I've see the same setup with everything go for $65.00 to $125 or hit local salvage yards. 4.3s were in 1/2 p/us vans & cars.

Ok, well that answers all the questions except one. Since this motor came with a serpentine belt system and thus a reverse flow water pump, will it hurt the motor if I keep the stock look and my original V-belts? Is the reverse flow absolutely necessary for the operation of the motor? I do like the stock look, but...I may go with a serpentine set up. The main reason I would stay with the V-belts, is all the accessories that I have are Vbelt...AC, power steering etc.

Ok, well that answers all the questions except one. Since this motor came with a serpentine belt system and thus a reverse flow water pump, will it hurt the motor if I keep the stock look and my original V-belts? Is the reverse flow absolutely necessary for the operation of the motor? I do like the stock look, but...I may go with a serpentine set up. The main reason I would stay with the V-belts, is all the accessories that I have are Vbelt...AC, power steering etc.

No, No, NO!

Get all this reverse flow stuff out of your head. Only LT1/LT4's are reverse FLOW. However all serpentine belt systems use a reverse ROTATION water pump. There is a HUGE difference!!! The Vortec engine you have is a STANDARD FLOW REVERSE ROTATION water pump. If you want to run V-belts you will need a STANDARD FLOW STANDARD ROTATION water pump (aka one from a 55-86 Chevy).

Next you need to decide if you want to run a short or long water pump...

Get all this reverse flow stuff out of your head. Only LT1/LT4's are reverse FLOW. However all serpentine belt systems use a reverse ROTATION water pump. There is a HUGE difference!!! The Vortec engine you have is a STANDARD FLOW REVERSE ROTATION water pump. If you want to run V-belts you will need a STANDARD FLOW STANDARD ROTATION water pump (aka one from a 55-86 Chevy).

Next you need to decide if you want to run a short or long water pump...

Oh...Well that finally answered the question that I tried to ask in my first post and I didn't know know they were two separate entities.

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